The invention relates to devices and methods for repair and patching damaged plaster or drywall, which is sometimes referred to as sheetrock. Drywall, a material made of plaster of Paris or the like sandwiched between two cardboard sheets, is attached, in the form of panels, to two by four studs which are arrayed on 16 inch centers. But drywall is quite brittle and can be easily damaged. A sharp corner of a piece of furniture can easily gouge a hole in drywall.
In the past, the repair of a hole in drywall included placing a backing plate behind the drywall and then filling in the hole with a spackling compound or with plaster of Paris. This method of repair requires a plurality of steps that can span several days. A day or so is needed just for the original filling material to dry. But during the drying process, some shrinkage usually occurs. The patch must then be sanded and a second layer of filling material applied to level the hole. After another day or so, the patch on the wall is finally ready to paint.
Patches, which can be used to simplify construction, are also known. Hoffmann, U.S. Pat. No. 4,135,017, discloses a patch strengthened by a thin gage aluminum sheet which can be bonded to a wall using a two-sided adhesive tape. The exterior surface of Hoffmann's patch is covered with a fibrous material of sufficient porosity to allow a wall finishing compound to be bonded to it. To effect a smooth and virtually invisible repair, one must cover this fibrous material with a thin coating of plaster. Although the Hoffmann invention is an improvement over past methods, it still takes a long time to apply because the coating of plaster must be allowed to dry.
A device for repairing of holes in drywall which does not need to be coated with plaster is described in copending U.S. patent application Ser. No. 262,703 filed by Owens and McClellan. This device comprises a patch that can be applied to cover a hole in a wall, after which the area can be immediately repainted. The patch has an elastic body made from a semi-porous, rubber-like material which is capable of retaining a film of paint and which is backed by a pressure sensitive adhesive tape. Because this earlier device has an elastic body, it is best suited for use in covering relatively small holes.